21116403 has 48 divisors (see below), whose sum is σ = 39726720. Its totient is φ = 10962000.

The previous prime is 21116401. The next prime is 21116411. The reversal of 21116403 is 30461112.

It is a happy number.

21116403 is a `hidden beast` number, since 21 + 1 + 1 + 640 + 3 = 666.

It is not a de Polignac number, because 21116403 - 2¹ = 21116401 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21116401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 13828 + ... + 15278.

It is an arithmetic number, because the mean of its divisors is an integer number (827640).

Almost surely, 2^21116403 is an apocalyptic number.

21116403 is a deficient number, since it is larger than the sum of its proper divisors (18610317).

21116403 is a wasteful number, since it uses less digits than its factorization.

21116403 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1485 (or 1472 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 21116403 is about 4595.2587522358. The cubic root of 21116403 is about 276.4012358901.

Adding to 21116403 its reverse (30461112), we get a palindrome (51577515).

The spelling of 21116403 in words is "twenty-one million, one hundred sixteen thousand, four hundred three".